/***********************************************************************
 * BinTrotter : BitTorrent library/client for the Android operating system.
 *  
 * Copyright (C) 2009, Christopher David Stones (chris.stones@gmail.com)
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 ***********************************************************************/

package org.bintrotter.afiles;

import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.MappedByteBuffer;
import java.nio.channels.FileChannel.MapMode;

public class File {

	public final long streamAddress;
	public final long size;
	
	private RandomAccessFile raf;
	private java.io.File file;
	
	public File(java.io.File file, long streamAddress, long size) throws IOException {
		
		this.file = file;
		this.streamAddress = streamAddress;
		this.size = size;
		this.open();
	}

	public MappedByteBuffer mmap(long addr, long len) throws IOException {
		
		return raf.getChannel().map(MapMode.READ_WRITE, addr, len);
	}
	
	public void open() throws IOException {
		
		if(raf == null)
			raf = new RandomAccessFile(this.file,"rw");
		
		if(raf.length() != size)
			raf.setLength(size);
	}
	
	public void close() throws IOException {
		
		raf.close();
		raf = null;
	}	
}

